ML20090J688

Proposed Tech Specs Deleting Two Primary Containment Isolation Valves of Head Spray Line & Revising Description for Penetration to Indicate That Line Being Capped Off. Justification & Safety Analysis Encl

ML20090J688
Person / Time
Site:	Browns Ferry
Issue date:	05/10/1984
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20090J680	List: ML20090J678 ML20090J688
References
NUDOCS 8405230138
Download: ML20090J688 (6)

Text

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ENCLOSURE 1 PROPOSED TECHNICAL SPECIFICATION REVISIONS TVA BFNP TS 195 SUPPLEMENT 1 8405230138 840510

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PDR P ADr)CK 05000296 PDR

TABLE 3.7.A PRIMARY CosFAIsttDIT ISDIATION VALVES Action on **

• pomber of somer Maminum poraal Initiating operated Valves ., operating Signal Inboard outboard Time (sec.) Position Group Valve Identification 3<T<5 0 GC 4 4 1 main steam 11ae isolation valves (FCV 14, 26, 37, & Sl; _

1-15, 27, 38 5 52) CC 15 O

1 1 1 Main steamline drain isolation valves (FCV-1-55 & 1-561 sc 1 5 C ,

Reactor water sample line isola- 1 1

tion valves 2 RERS shutdown cooling supply 1 40 C SC

, 1 isolation valves (FCV-74-48 8 47) SC 2 30 C 2 RERS - LFCI to reactor (FCV-74-53 & 67) 4 2 RERS flush and drain vent to 4 20 C SC M suppression chamber ,

• • (FCV-74-10 2, 103, 119, & 120) 15 C SC 2

2 Suppression Chamber Drain (FCV-75-57 8 58) .

2 Drywell equipment drain discharge 2 15 0 GC isolation valves (FCV-77-15A 5 158) e 2 Drywell floor drain discharge 2 15 0 GC ,

isolation valves (Fcv-77-2A C 25) t e

TABLE 3.7.C r

TESTABLR PENETRATIONS WITH TESTABLE BELI4WS 6,

X-7A - Primary Steamline X-11 -

Steamline to HPCI Turbine X-7B - Primary Steamline X-12 -

RHR Shutdown Supply Line X-7C -

Primary Steamline X-13A -

RER Return Line X-7D -

Primary Steamline X-13B -

RER Return Line X-8 - Primary Steamline Drain X-14 -

Reactor Water Cleanup Line X-9A -

Feedwater Line X-16A -

Core Spray Line X-9B -

Feedwater Line X-16B -

Core Spray Line X-10 - .

Steamline to RCIC Turbine X-17 - ' Blank r

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TABLE 3.7.F .

PRIMARY C0tfrAIf32iir ISOLATION VALVES LOCATED IN ITATER SEALED SEISMIC CIASS 1 LDES Valve Valve Identificatio'n 7h-53 RIE LIC; Discharge 1

7 4-54 RIE 7 14-57 ,

RHR Suppression Chamber Spray 74-58 rim Suppression Chamber Spray 7h-60 RER Dryvell Spray 7h-61 R11R Drywell Spray 74-67 1 Rim LICI Discharge 74-00 Rim LICI Discharge "Is'71 R:R Suppression Chamber Spray "k-72 RHR Supprescion Charnber Spray 7h -14 RIS Drywell Sprt,y "h ~5 RHR Dryvell Spray 75-25 Core Spray Discharge 75-25 Core Spray Discharge -

, 75-53 Core Spray Discharge 75-54 Core Spray Discharge

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• ENCLOSURE 2 JUSTIFICATION AND SAFETY ANALYSIS (TVA BFNP TS 195 SUPPLEcENT 1)

The head spray line was designed to remove decay heat and residual heat from the reactor during normal shutdown and couldown. When the reactor is cooling down, part of the residual heat removal flow may be diverted to a spray nozzle in the reactor head. This spray maintains saturation conditions in the reactor vessel head volume by condensing steam being generated by the hot reactor vessel walls and internals. This operational mode has never been used at Browns Ferry.

The head spray line is provided as an operational option. The head spray is not used in any accident analysis, and no credit is taken for having the head spray line in order to safely shut down the plant in the event of an accident. In fact, this line is isolated on an accident signal. It isolates on reactor low water level, high-drywell pressure, and reactor pressure greater Uman 100 psig. .

By removing the head spray line, the number of possible breach paths from the reactor vessel and from the containment is reduced. This will result in a decrease in the probability of an accident resulting from a pipe break or a breach in primary containment. Since the system is not used for accident mitigation, its removal will not result in an increase in the probability of an accident or thm severity of any known accident; therefore, the overall result of removing the head spray line would be an increase in the margin of safety.

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'N ENCLOSURE 3 PROPOSED NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION BROWNS FERRY NUCLEAR PLANT UNIT 3 (TVA BFNP TS 195 SUPPLEMENT 1)

Description of Change 4

The proposed amendment would delete the two primary containment isolation valves of the head spray line and revise the description for the penetration to indicate that the line is being capped off. The changes are the result of removing the head spray line from the vessel head to just inside primary containment.

Basis for Proposed No Significant Hazards Consideration Determination The head spray line was designed to remove decay heat and residual heat from the reactor during normal shutdown and cooldown. When the reactor is cooling down, part of the residual heat removal flow may be diverted to a spray nozzle in the reactor head. This spray maintains saturation conditions in the reactor vessel head volume by condensing steam being generated by the hot reactor vessel walls and internals. This operational mode has never been used at Browns Ferry.

The head spray line is provided as an operational option. The head spray is not used in any accident analysis, and no credit is taken for having the head spray line in order to safely shut down the plant in the event of an accident. In fact, this line is isolated on an accident signal.

It isolates on reactor low water level, high-drywell pressure, and reactor pressure greater than 100 psig.

The proposed amendment will not involve a significant increase in the probability or consequences of an accident previously evaluated. By removing the head spray line, the number of possible breach paths from the reactor vessel and from the containment is reduced. This will result in a decrease in the probability of an accident. The proposed amendment would not create the possibility of a new or different kind of accident from any previously analyzed since the system is not used for accident mitigation and no credit is taken for it in any accident analysis.

Therefore, the overall result of removing the head spray line would be an increase in the margin of safety.

Based on the above analysis, TVA proposes to determine that the proposed amendment doese not involve a significant hazards consideration.

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